The present invention relates to telephony systems and, more particularly, to a telephony system that enables telephony service providers to use various Intelligent Network services.
With the growing need to respond to a wide variety of requirements for communications, consideration has been directed toward making networks highly intelligent. Hence, the IN (Intelligent Network) has been proposed for this purpose.
An Intelligent Network (IN) is a service-independent telecommunications network. That is, intelligence is taken out of the service switching point (also referred to as SSP) and is handled by service control points (SCP) where the service logic is located. This provides the network operator with the means to develop and control services more efficiently. In such an IN, a plurality of intelligent peripherals (will be abbreviated to IP) and pluralities of vender feature nodes (VFN) are used as terminal devices.
Each of the terminal devices is connected to a service control point (SCP) through a service switching point (SSP), which is operable in a manner similar to a conventional exchange system. Each of the SCPs is managed by a service management system (SMS), which has a database. Having the service control points located separately from the switching facilities allows services to be added or changed without having to redesign switching equipment.
By way of illustration, a call handling procedure in a conventional IN based prepaid system is performed as follows:                A prepaid subscriber dials a number that is received by a service switching point (SSP) at the telephone company central office.        The SSP detects the event and sends a query request to the SCP based on the call source and destination and additional billing rules located in the database.        The SCP returns the SSP corresponding charging parameters and the maximum call duration allowed. If the subscriber's balance is lower then the amount required for making the call, the call request is denied. Otherwise the SSP connects the subscriber to the destination requested, and upon termination of the call a charge request sent to the SCP.        Other examples of services that may be provided by SCP include area number calling, disaster recovery and do not disturb services.        
The SSP communicates with each SCP by transmittal of a service control request message (from the SSP to the SCP). The SCP executes a call control operation, which provides service to a user connected through the SSP. The call control operation is determined by the service control request message.
Therefore, in conventional Intelligent Networks, the SCP should be designed to respond to the service control request message and to provide the service to each user as long as the service control request message has the format determined for the SCP.
In practice the SSP may not always be connected to terminal devices that have the service control request message of the same format, but may be connected to a plurality of terminal devices that are different in species from one another. In this case, the SCP is supplied from each of the terminal devices through the SSP with service control request messages of format that are different from one another in order to specify the species of the terminal devices.
In addition, at times, a new model SSP may partially substitute an old model of SSP, both of which may be connected to the same SCPs. According to prior art it is impossible for an SCP to communicate with both SSPs.
Hence, in conventional Intelligent Networks, each SCP can neither respond to different service control request messages nor cope with the coexistence of the old and the new model SSPs. Simply put, each user (SSP) is designed to communicate with one specific SCP.
This situation, whereby an SSP can only be defined to communicate with a specific SCP, creates a limitation for telecom providers. A company providing telecom services, which has purchased an Intelligent Network platform from a certain vendor, will probably need to purchase all additional Intelligent Network services and solutions from the same vendor. For example, if a telecom service provider has purchased an Ericsson switchboard he would be obliged to use Ericsson SCP to supply the additional Intelligent Network solution
This limitation becomes more acute when the same telecom provider is interested in an additional service that only a second vendor can provide. In this case, the telecom provider would not be able to purchase additional services since the provider's SSP can only send the request to the originally defined SCP.
A possible way to get round the limitation created by the prior art is to relate the Intelligent Network service to designated numbers rather than to a specific user. The problem created using this solution is that the telecom provider would not be able to relate each service to a destination number but to a range of numbers, making the procedure impossible to manage.
Another deficiency of the prior art Intelligent Network service configuration is that two different services can't be integrated. For example, if a virtual number service and prepaid costumer service are from different equipment providers, the operator is unable to provide integrated service, thus the operator needs to build a new integrated service.    IN platforms are complex systems and require in-depth understanding of their architecture and protocols. Although IN standards such as CS-1 and CS-2 were defined and accepted by the industry, each switch vendor enhances its protocol so more capabilities can be added. Newer standards such as CAMEL and PARLAY are not yet widely adopted by the industry and it will take the vendors a few years to implement and market them. This makes things more difficult and more complicated for IN solution developers.    Prepaid systems are closed systems. They do not provide any open API for third party developers in order to integrate with these systems and exploit the capabilities of prepaid infrastructure. Thus many Data and Value Added Services (VAS) providers are not able to integrate to prepaid systems and are unable to offer these services to prepaid subscribers.    Telecom operators invest millions of dollars and a great deal of time in buying, assimilating and operating prepaid systems. Replacing or upgrading these systems is done every few years due to the high costs involved. Thus telecom operators are looking for a low cost solution that can offer an easy way to interconnect Data and VAS with the prepaid systems, thus enabling them to maximize revenues from existing and new services.    Telecom operators invest time and money in developing services that cannot communicate with one another. In order to provide integration of different services, the operators need to buy a new service and manage plural provisional databases.